1. Field of the Invention
This invention relates to hot spots in logical arrays and more particularly relates to relocating hot spots.
2. Description of the Related Art
Storage systems often store large amounts of data across a plurality of storage devices. For example, an enterprise data processing system may store data such as transaction data, customer accounts, customer accessible product information, and the like on hard disk drives.
The capacity of the storage devices may be divided into logical segments. The logical segments may be organized into one or more logical arrays. A logical array may also be referred to as a rank.
Some logical arrays may be accessed much more frequently than other logical arrays. For example, a logical array storage device storing customer transaction data may be accessed much more often than a storage device storing personnel files. As a result, the latency of a heavy accessed storage device may degrade, while the latency of a lightly accessed storage device may remain acceptable.
Heavily accessed areas of a storage device are referred to herein as hot spots. Hot spots may not always be apparent because of the organization of the storage devices as logical arrays and logical segments. As a result, performance of a logical array may degrade because of excessive accesses to a hot spot although accesses to the overall logical array are not excessive.